Question :
41) 15.0 g of Cu combined with 46.0 g of : 1282398
41) 15.0 g of Cu are combined with 46.0 g of HNO3 (molar mass = 63.02), according to the reaction
3 Cu + 8 HNO3 3 Cu(NO3)2 + 2 NO + 4 H2O
Which reactant is limiting, and how many grams of H2O are produced?
A) Cu, 3.79 g
B) Cu, 5.67 g
C) HNO3, 0.737 g
D) HNO3, 6.13 g
42) The brown color of smog is due to the presence of nitrogen dioxide, NO2. Nitrogen monoxide, a by-product of combustion of fossil fuels, reacts with oxygen to produce NO2 in the atmosphere:
2 NO + O2 2 NO2
If 0.65 mole of NO is reacted with 0.75 mole of O2 to produce NO2, the limiting reactant is ________.
A) both NO and O2
B) O2
C) NO
D) Insufficient information given to determine which species is the limiting reactant.
43) If a mixture containing 0.80 mole of A, 2.1 moles of B, and 1.6 moles of C is allowed to react according to the equation
2 A + 4 B + 3 C 4 D + 2 E
A) A will be the limiting reactant.
B) B will be the limiting reactant.
C) both A and B are the limiting reactants.
D) C will be the limiting reactant.
44) If 30 slices of bread, 26 slices of cheese, and 38 slices of ham are available to make ham-cheese sandwiches according to the parameters given below,
1 slice of ham + 2 slices of cheese + 2 slices of bread 1 ham-cheese sandwich
How many ham-cheese sandwiches can be prepared?
A) 15
B) 16
C) 30
D) 13
45) Carbon monoxide is reacted with oxygen and converted to carbon dioxide by the catalytic converter on automobiles: 2 CO(g) + O2(g) 2 CO2(g)
Depicted below is a representation of a mixture of CO and O2 in a catalytic converter (at the molecular level). The gray spheres represent oxygen atoms and the black spheres represent carbon atoms. For the mixture shown below, which species is the limiting reactant?
A) CO2
B) CO
C) O2
D) Insufficient information given to determine.
46) Depicted below is a cylinder containing a mixture of N2 and H2 gas. The solid spheres represent hydrogen atoms and the lighter-shaded spheres represent nitrogen atoms. Nitrogen and hydrogen react to form ammonia, NH3, according to the reaction below.
N2 (g) + 3 H2 (g) 2 NH3 (g)
Choose the response that represents the contents in the cylinder if the reaction mixture is permitted to go to completion.
A)
B)
C)
D)
47) Tin metal is reacted with hydrochloric acid according to the following equation. If 0.240 moles of Sn is reacted with 0.320 mol of HCl, calculate the mass of hydrogen gas liberated.
Sn + 2 HCl H2 + SnCl2
A) 0.323 g
B) 2.79 g
C) 0.485 g
D) 1.31 g
48) In a certain experiment 24.9 g of NH4NO3 (molar mass = 80.06) was produced from 27.2 g of Fe(NO3)3 (molar mass = 241.88) reacting with an excess of NH3 and H2O according to the equation
Fe(NO3)3 + 3 NH3 + 3 H2O Fe(OH)3 + 3 NH4NO3
What is, respectively, the theoretical yield and percent yield of NH4NO3?
A) 5.53 g and 42.1%
B) 13.5 g and 83.7%
C) 16.6 g and 31.7%
D) 27.0 g and 92.2%
49) In a certain experiment using Ca and an excess of F, 10.6 g of CaF2 is obtained. This represents a 76.4 percent yield. What is the theoretical yield of CaF2 for this experiment?
A) 13.9 g
B) 12.6 g
C) 14.1 g
D) 15.7 g
50) Which statement concerning yields is correct?
A) Percent yield is the ratio of the actual yield to the theoretical yield times 100%.
B) Theoretical yield is the difference between the calculated yield and the actual yield.
C) Actual yield is the calculated amount of product that can be obtained from a given reaction.
D) In most chemical reactions, the amount of product isolated is larger than the theoretically possible amount.
